Saw-grinding machine



I. P. HEDSTRO-MQ SAW GRINDING MACHINE.

APPLICATION FILED JUNE 28.1920.

1,401, 9 Patented Dec. 27, 1921.

6 SHEETS-6H5 I.

M mIIII (/0290 A Heads-13mm flfiorney J. P. HEDS-TROM.

SAW GRINDING MACHINE.

APPLICATION man JUNE 23,

1,401,696, Patented De0.27,1921.

6 SHEETS-SHEET 2.

//7 yen/2m fl efm h orne m3. HEDSTROM.

v SAW GRINDING MACHINE. APPLICATION FILED JUNE 28.1920. I 1,401,696. Pat nted Dec. 27,1921.

' 6 $HEETS-SHEET 5.

I 55 7 m a [90/77 229 2 yMfW nice.

JOHN P. nnnsrnon. or BIG names, MICHIGAN, as'srcnon fronnonnvnnv. com any I or annarce, or are R'AIIDS, MICHIGAN, A conronarron or MICHIGAN..-

SAW-GRINDING MACHINE.

Specification of Letters Pa tent.

Application filed runezs, 1920. semi 1%. 392,311.

To aZZ whom it may concern:

Be it known that I, JOHN P. Hnns'rnoina citizen of the United States of America, residing at Big Rapids, in the county of Mecosta and State of Michigan, have invented certain new and useful improvements is Saw-Grinding Machines; and I do present invention to construct a saw grinding machine by means of which saws, irrespective of'their condition. may be ground so as to place them in-perfect serviceable condition; in fact the saw may be totally unfit for use and with the machine of my invention be brought back to perfect shape, the machine having a range of use such that a perfectly plain disk might be fullyprovided with a consecutive series of saw teeth by its use. A furtherobject of the invention is to provide a machine of this character by means of which the teeth of a saw may be ground in succession one after the other, and after all of the teeth have been ground the same, the saw'is automatically changed in position with reference to the grinding wheel for a further grinding of the teeth, said automatic changing occurring each time the whole series of teeth on the saw have been ground the same, or with each complete turning of the saw and grinding of each tooth thereon. A still further object of the invention is to provide such machine with various adjustments whereby saw teeth of different characters may be ground, practically any type of saw being taken care of in the one machine, and any size or shape of tooth being ground thereon. Many other objects and purposes than those specifically stated will appear fully and in detail as unlerstandin of the invention is had from the following description, taken in connection with the accompanying drawing, in which,

Figure 1 is a front elevation of the saw grinding machine. I

Fig. 2 is a side elevation'thereof.

Fig. 3 is a vertical section through the casin orhousing for theop'erating mechanism of themachine, said section being immediately back of the front side of the housing and parallel thereto. I 4 ig. 4. is a similar section ina plane: paratented Dec. 27, 19 2 1.-

allel to the plane ofthesection of Fig. 8

but back thereof.

Figs 5 and 6 are" sections taken, respectively, online s 55-and 6-6, of Fig. 4:. i

Fig. 7 is a section showing-the rear side of said housing removed and looking-atthe mechanism from being shown.

.Fig. 8 is a fragmentary section on the plane of line 8 8, of Fig; 7.

the rear, certain parts not 'Fig; 9' is a fragmentary side elevation'of the'upper part of the housing, illustrating a detail ofconstruction used 'for stopping the feed of the grinding wheel While the machine is in operation.-

F ig. IOis a fragmentary enlarged vertical section through the mount for the saw and its coiiperating ratchet disk. i

Fig. 11 is a fragmentary front elevation of the machine, certain parts being removed to show thestructure back of the saw.

Fig. 12 is a vertical enlarged Section through the upper part of the head of the disk operating lever. i

- Fig. 18 is a similar section taken at right angles to the plane of the section shown in Fi 12. V

Fig. 14: is a side elevation of a part of the automatic upward feed mechanism'for elevating the saw at the completion of each cycle of grinding.

Fig. 15 is a horizontal section taken through the housing above the cross shafts therein, various parts of; the mechanism not being shown in the view; h

Fig. 16 is a fragmentary vertical section and side elevation showing the movable mounting for the grinding wheel shaft, and Fig. 17 is a rear elevation thereof.

Like reference characters refer to like had. V

A shaft 9 is mounted in bearings 9- at 'the upper ends of supporting brackets 10 carried at the rear of and extending upwardly from the housing as shown in Fig. 2. On this shaft two pulleys 11 and 12 are located, one of which is loose, and the drive belt from any suitable line shafting or other source of power passes around the same, being shiftable from one to the other in the usual manner. The shaft also carries drive pulley 13 around which a belt 14 passes, it also passing around a pulley 15 on a shaft 16 mounted in bearings l6 formed at the front ends of forwardly extending arms 17 cast integral with a plate 18 which is mounted for vertical movements on a post 19 secured at its lower end to the upper side of and at the front of the housing. A grinding wheel 20 is secured at the inner end of shaft 16. This wheel is removable and may be replaced at any time by others for the grinding of different sizes and types of saw teeth.

An arm 21 extends rearwardly from the plate 18 through which a rod 22 passes, being provided with an operating head 23 at its upper end and with a collar 24 on which the arm 21 rests. The lower end of rod 22 is threaded and passes through a nut 25 swivelly mounted in an enlargement 25 on a lever 26 pivotally mounted at one end at 27 within the housing. At its opposite end lever 26 carries a shoe 28 pivotally mounted at- 29 on the lever. A coiled spring 30 under compression is disposed between the upper end of the shoe and the enlargement 25 and a screw 31 threads through a laterally ofiset lug 32 on the lever against the shoe. The screw extends through a slot 33 in the side 5 of the housing and is equipped with an operating head 34 by means of which the positionof the shoe may be adjusted from outside the housing.

Shaft 9 carries a small drive pulley at one end around which a belt 36 passes, the same also passing around a wheel or pulley 37 fixed at one end of a shaft 38 which is mounted in and passes through a casing 39 attached at the rear of the housing. A beveled gear 40 on shaft 39 meshes with a similar larger gear 41 fixed at the end of shaft 42 which passes into and through the housing for steady bearing support. A pinion 48 on shaft 42 drives a gear 44 on a second shaft 45 parallel with shaft 42 as shown in Fig. 15. Two cams 46 and 47 are mounted in fixed relation on the shaft 45.

A lever 48 is pivotally mounted at 49 at its lower end in the housing and extends upwardly over the cam 46, carrying a roller which rides on the cam. At its upper end it carries a rooved roller 51 which is adapted to engage with the under side of shoe 28, the shoe being shaped to fit the grooved i ,aoneec roller to prevent disengagement therefrom. It is evident that with each revolution of the shaft 45, the lever 48, and also the lever 26 is raised and lowered once with a consequent raising and loweringv of plate 18, shaft 16 and the grinding wheel 20 attached to the shaft, and that the amount of this movement may be adjusted within limits by changing the position of the shoe 28 through operation of the adjusting screw '31.

A second lever 52 is mounted at one end on a pivot in the housing and extends across and above the shaft 45 and on a downwardly projecting portion 52 thereof .a roller 54 is mounted which rides on the cam 47, being held against the cam by a spring 54 At its freeend the lever carries a grooved roller 55 which bears against a shoe 56 pivotally mounted between its ends at 57 on a vertically positioned arm 58 which is pivotally mounted at 59 at its lower end within the housing and which extends above the housing, passing through slot 60 in the top 3 thereof. The arm 58 is normally drawn toward the side 4 by spring 61. An adjusting screw 62 threads through a nut 63 swivelly carried at the up per end of the shoe 56 and is operatively connected at its inner end at 64 with the arm 58, the screw passing outwardly through an opening in side 4 and having an operating head 65 attached to its outer end. On turning said screw, the position. of the shoe 56 is changed with a consequent changing of the extent of swing of the arm 58 with each revolution of the shaft 45 as is evident.

The head 56 of arm 58 is enlarged and formed with an opening rectangular in cross section therethrough in which a bloclr 66 is adjustably mounted, the same being flanged at one side to bear against a side of the head and held in place by a plate 67 detachably connected to the opposite side of the blot-l1. in adjusting screw 6-8 threads through the block and is rotatably mounted on the head, being equipped with an operathead 69. Turning the screw shifts the position of the block with reference to the head 58*. A bolt 71 passes through the block 66 and plate 67 on which a member is pivotally mounted. A red 72 passes through the member 70 above the pivotal mount therefor and is adjustably connected thereto by a set screw 73. Normally the rod 72 is yieldingly held in a lower position by the tension of spring-'74 attached thereto and to the arm 58 as shown in Fig. 11. I

The rod 72 at a distance from the member 7 O is turned forward. so as to engage with a disk 75 provided with a consecutive series of ratchet teeth equal in number to the teeth on the saw 76 with which it is asso ciated. The ratchet disk and the saw are secured on a sleeve 77, the disk backing against a flange77 thereon. Between the disk and spacing collar 78 is placed and a similar collar 78 lies against the outer side oft-he saw, all being securely but detachably' connected together by a binding nut 79 "threadedonto the end of the. sleeve.

disk "'75- should be approximately somewhere near the saw 76 in diameter for the best restilts, though the machine works satisfactorily with a smaller ratchet disk so long as the number of teeth therein equals the num 'berof teeth in the saw.

' The assembly of ratchet disk and saw is placed over a stationary'arbor 80. A coiled .spring 81 bears against awasher 82 placed over the arbor and against the end of sleeve 77' and may be more or less compressed by nut 83 threaded on to the end of the arbor as shown in Fig. 10. The arbor is designed to be secured at the upper end of a supportingmember 84: which is mounted for sliding adjustment on a horizontal slide bar 85 and which is held in any position to which it may threading into the bar 85 is mounted vertically at the front of the housing passing through a bracket 89 attachedto the under side of the housing and held-from vertical movements by set collars thereon one above and the other. below the bracket. "A beveled gear 90 is secured to the lower end of the shaft and is in mesh with a similar gear 91 attached at one end of a horizontal shaft 92 mountedon and carried by downwardly extending arms 89 and 89 of the bracket 89. A ratchet-wheel 93 is secured on shaft 92 between its ends and at the outer end a crank 94: is attached for manual operation of the shaft with a consequent raising or lowering of the bar 85 and the parts mounted thereon.

A rod 95 is positioned vertically in front of the housing, passing downwardly through abracket 96 attached to and extending in front of the front 7 of the housing. A dog 97 adjustably connected adjacent the lower end of the rod and held in position on the rod by a screw 98 engages with the ratchet wheel 93. A spring 99 is located around the rod 95 above bracket 96, hearing at its lower end on said bracket and its compression force may be regulated through adjustment of the member 100 attached adjustably on the rod at the upper end of the spring and held in position by the screw 101. Red 95 at its upper end is pivotally connected to one end of a bar 102 which is positioned sub stantially horizontal and which at itslopposite end is pivotally connected at 103 to the slide bar 85. The disk 7 5 has a pin 104 secured thereto and extending rearwardly,

this pin in each revolution of the disk coming against the upper side o'fbar'102 anddepressing it with a consequent downward movement of rod 95 and operation of shaft 92 and connected parts thro'ug'h'thleengagement of pawl 97 with the ratchet wheel 93.

A latch bar 105 is pivotally mounted at one 'end at 106 on the side 5 of the housing and may be hftedtonpper horizontal position, as shownin Fig. 9, a handle or knob 107' for manual operation being attached to its free end. It may be held in'such upper position through engagement with the projection 108 on the side 5 in which case ad- 'justing'screw 31 will not be permitted to drop and lever '26 is held in upper position, no downward feed of the grinding wheel 20 taking place though the machine is running.

Any size ofsaw may be placed with its accoriipanying ratchet disk on the arbor and the proper position for it with reference to the grindingwheel obtained by turningthe crank 94. The character of the teeth ground may be regulated by moving the member 84: on the slide bar to the desired position, together with the selection of the right shape of grinding wheel. The finer adjustment of the wheel with TGfT8I16 to the saw is secured through turning the, rod 22 to raise or lower the wheel. The extent of downward feed ofthe wheel may be regulated through operation of adjusting screw 31. The swing of the arm 58 and ronsequent adjustment for the pawl 72 for different ratchet disks is regulated through operation of adjusting screw 62. together with an adjustment of the block 66 through screw 68. lVith these various adjustments the machine may be fitted to grind any type and size of saw within the limits of thesizn of the machine. 7

After the adjustments for a saw are made and the machine is ready to start operation, the belt may be shifted from the loose to the fixed pulley on shaft 9; The wheel 20 will be drivenata very rapid rate and shaft 4L5 at a much slower rate-of speed. With each rotation of shaft e5 the grinding wheel is raised and lowered, grinding the saw tooth below it on its downward movement. lVith each rotation of the shaft there is also a movement of the arm 58 and engagement of the pawl rod 72 with ratchet disk 7 5 to move it and the saw with it to a new position for only at the later cycles of grinding or when the grinding is nearly finished. In the first cycle the grinding wheel is to pass only partly down between the teeth, each tooth. receiving the same treatment. iVith the completion of the cycle which turns the ratchet disk ?5 and the saw 76 through one complete revolution, the automatic opera-- tion of bar 102 and attached mechanism by pin 10%, causes a slight elevation of the saw carrying members, so that with the next cycle, the teeth are further ground; and this continues until the teeth are fully and completely ground and sharpened. It is evident, of course, that the condition of the saw to be ground will govern the number of cycles necessary for the proper grinding and that the extent of elevation of the saw with each cycle completed may be governed by the position of the pin 104- on the disk 75, its distance from the center of the disk and the amount that it depresses lair N32 with each revolution. It is clear that the degree of damage which the saw may have suffered is not of importance except for using the proper adjustments therefor, as the machine is capable of grinding and sharpening saw slightly out of perfect condition to those so badly damaged as to be entirely worthless. In fact with a plain disk in place of the saw 76, it is readily possible to automatically make a complete and finished saw with any character of tooth desired, either as to shape, number, and depth.

The construction disclosed is practical and operative and has proven its practical usefulness over a considerable period of time. The invention is defined in the pended claims and I consider myself entitled to all forms of structure coming with in their scope and do not wish to be limited to the exact structure shown and described.

I claim: 7

1. In a saw grinding and sharpeningjmachine, means for rotatably supporting saw, means for periodically turning the saw on its support by step by step movement to bring a succeeding saw tooth into the position occupied by the next preceding saw tooth, a rotatably mounted grinding wheel, means for driving the same, means for periodically moving the grinding wheel to ward and away from the saw, means for automatically elevating the saw after all of the teeth thereon have been acted upon by the grinding wheel, substantially as described.

2. In a saw grinding and sharpening ma chine, means for rotatably supporting a saw, means for successively grinding each tooth thereon, and means for automatically elevating the saw after all of the teeth have teeth from those only ac ose been ground tobringthe same nearer the grinding wheel to thereby grind the teeth a greater distance in the succeeding cycle of grinding, substantially as described.

3. in a saw grindingand sharpening machine, a rotatably mounted saw, a grinding wheei, means for driving the same, means for periodically moving the grinding wheel toward and away from the saw, means for periodically turning the saw to bring successive teeth thereof into position to be acted upon by the grinding wheel, means for yieldingly securing the saw against rotative movement, and means for moving the saw toward the grinding wheel between successive cycles of grinding all of the teeth of the saw, substantially as described.

in a saw grinding and sharpening ma chine, means. for rotatably supporting a saw, a grinding wheel, means for driving the same, a ratchet disk connected with the saw and having the same number of teeth, means for periodically moving the grinding wheel toward and away from the saw, an operating rod engaged with the ratchet disk, and means for periodically moving said rod back and forth to thereby move the disk and associated saw one step, substantially as described. v j

5. In a saw grinding and sharpening machine, a support, a horizontal slide bar mounted thereon for vertical adjustment, a member mounted on the slide bar for hori zontal adjustment, a saw rotatably mounted on said member, a grinding wheel rotatably mounted on the support above the saw, means to drive the same, means for periodically moving the grinding wheel toward or away from the saw, means for periodically turning the saw step by step to bring successive teeth into position to be acted upon by the grinding wheel, and means for automatically elevating the slide bar between cycles of grinding the teeth of the saw, each cycle comprising a grinding of each tooth by the wheel, substantially as described.

6. in a saw grinding and sharpening machine, a support, a horizontal slide bar mounted thereon for vertical adjustment, a member mounted on the bar for horizontal adjustment, a saw rotatably mounted on said member, a grinding wheel rotatably mounted on the support above the saw, means to drive the same, means for periodically moving the grinding wheel toward or away from the saw, means for periodically turning the saw step by step to bring successive teeth into position to be acted upon by the grinding wheel, a shaft threaded into the slide bar and means for automatically turning said shaft to elevate said bar between cycles of grinding the saw teeth, each cycle comprising a grinding of all of the teeth of the saw, substantially as described.

'7. In a saw grinding and sharpening machine,fa rotably'mounted saw, a diskhavin'g' ratchet teeth thereon equal in number to the number of teeth onthe saw, said. disk being: operatively connected with the saw, a grinding wheel rotatably mounted above the saw, meansto' drive the same, means for periodically moving the wheel toward and away from the saw, a pivotall pawl rod' attached to said arm and engaging.

' with the disk, and n eansi'or osoillatingsaid arm periodically about its pivot, to'thereby'.

: move the disk and associated saw one step between movements of the wheel toward the 'plate, a rotatably mountedbelow the grinding; wheel, and means for periodically turning said saw step by step to bring successive teeth thereof intoposit'ion tobe acted upon by the grinding wheel, combined with an arm extending from" the plate, a rod threaded, at its lower end, passingthrough thearm and havi'ngjthreaded connection at its lower end with'an element" of the means for periodically raising and lowering the grindingwheehj and acollaron the rod'on scribedi I v 9. In; a, saw

which said arm *res ts,"siibstantially as dechine,'thefcombination'ofa support,- a rota tably'j mounted grinding Wheel, means io'r driving the same, means for periodically lowering and raising the grindingwheel', a

, saw rotatably mounted on the support, a ratchet, disk operatively connected with the saw to turntherewith, said disk having the same number o'f'teethas the saw, a pin projecting from the disk, a support for the saw mounted for vertical adjustment on the first support, shaft mounted on the firstjsupport' and threaded into the sawsup'port, a

bar pivotally mounted on the saw support and extending horizontally so as to been gaged and depressed on each rotation of the disk, andmeans operatively connecting said bar and shaft "for partially turning the shaft to change the positionot the saw support 1 with each complete revolution of the disk' and associated saw, substantially as described. k

10. In a saw grinding and sharpening ma-' chine, the combination ofa support, a'grind- 7 ing wheel rotatably mounted thereon, means for driving the same, meansfor periodically lowering and raising the grinding wheel-,a-

member mounted for vertical adjustment on the suppor'ha saw rotatably mounted there on, a ratchet disk operatively conneeted'with mounted mm, a l

operated by'the movement of the bar-forele grinding and sharpening ma+ the sawrto turn therewith, said disk having the same number of teeth as -the;saw,"a pin extending from the disk, means engaging;

with the disk to periodically turn the same step by step between downward movements of the grinding wheel, a barpivotally n'iounted at oneendon said sawcarrying member, said bar being operated by the pin; with each rotation oi th'e' disk, and {means vating the saw carrying inember, substan-.

tial-ly as described. v

' 11; In a saw grinding and sharpening ma chine, the comblnationot a support, a grind;

ingwheel rotatably mounteclthereon, means for driving the same, means forperiod'ically lowering and raising the same, a member mounted for 'vertlcal adjustment on the,

support, a saw rotatably mounted on said member, a Iratchetdisk having the same number ofteeth as the saw operatively'com nectedwiththe saw to turn therewith, a -pin extending from the disk, means engaging with the disk teeth to periodically turnthe same step by step between downwardxniovements of the grinding wheehazbarpivotally mountedat one end onthe saw supporting member, a vertical 10a attached to the; 0p-

posite end of the bar, a b'raeket on the support through which the rod passes, a spring around the rod and 'restii'ig'on the bracket, means onthe rod] to adjust the compressive" force ofthe'spring, a pawl connected to the rod, at-horizonta-l shaft: 'rotatably 'Inoii ntedj' on the support, ratchet wheelth reonwith which saidpawl has engagement, v a vertical shaft mounted on the support andyha'v ing its upper end threaded into the saw' supporting member, and gearing connections between the two shafts substantially as described;

ing wheel rotatablymountedon and a'bove the housing, means to drive the same, means for periodically lowering and raising the grinding wheel, a saw rotatably'fmounted at the front of the housing below the grindl ing wheel, a ratchet disk oper'atively conQ nected with the saw to turn therewith, *sa-id' disk having-the same-"number of teeth as the saw,'-an arm pivojtally mounted at its lower end within the housing and extend- 1ng;throughthe-t0p thereof,-. a'pawl rod "pivotallyxmounted-at the'upper end ofthe arm 'andgdisposed in engagement with the disk, and means for periodicallyoscillating said arm about its pivot to turn the disk and 12in a saw grinding and sharpening ma-i r chine, a hollow supporting housing, a grind} associated saw"between" 'downward move ments ofthe grinding wheel.

13. In a saw'gri di'ngand 'sharp'e'ning machine, a hollowsupporting housing, a grind mg wheel rotatably-mounted on and above the housing, means to drive the same,'meaus for periodically] lowering and raising the grinding wheel, a saw rotatably mounted at the front of the housing and below the grinding wheel, a ratchet disk operatively connected with the saw and having the same numberof teeth as the saw, an arm pivotally mounted at its lower end within the housing and, extending through the top thereof, a pawl rod pivotally mounted at the upper end of the arm and in engagement with the disk, a shaft extending through the housing, a cam thereon, a pivotally mounted lever within the housing equipped with a roller riding on said cam, spring means for holding the roller against the cam, a shoe attached to the arm, a roller on the end of the lever riding against said shoe to move the arm in one direction, spring means tending to draw the arm in the opposite direction, and means to drive the shaft, substantially as and for the purposes described.

1 1. A construction containing the elements in combination defined in claim 13 combined with means for adjusting the shoe to different positions on the arm from without the housing, substantially as described.

15. A construction containing the elements defined in combination in claim 13, in which said shoe is positioned vertically alongside of the arm and is pivotally mounted between its ends thereon, combined with an adjusting screw, a swivellednut carried by the upper end of the shoe and through whichthe screw passes, said screw extending outwardly through a side of the housin v I operating head on the outer end of the screw,

and means connecting the inner end of the screw to the arm, substantially as described.

16. In a'saw grinding and sharpening machine, a hollow housing, a post bn the upper side thereof, a plate slidably mounted on the post, a shaft rotatably mounted or the plate, a grinding wheel on the shaft, a shaft rotatably mounted in the housing, a. cam thereon, an arm. extending from the plate, a rod connected with the arm and passlng downwardly into the housing, a lever plvotally mounted in t 1e housing with which the lower end ofsaid rod has connection, a shoe on the end of the lever, a

second lever pivotally mounted within the housing and equipped with'a rollerriding on the cam, andfa roller on the end of said second lever engaging with the shoe where v by on each revolution of the second shaft the grinding wheel is loweredand raised, substantially as described.

17. construction containing the ele-' ments in combination defined in claim 16 and in which said shoe is vpivotally mounted on said. first lever, combined with means for-adiustinn; the shoe to different positions operable from without the housing.

18. A construction containing the element scribed.

in combination defined in claim 16 and in.

which said shoe is pivotally mounted on the first lever, of an adjusting screw, a laterally turned lug on the lever through which the. screw threads to bear against the shoe, said screw extending outwardly through a. slot 'inthe side of the housing, a spring acting against the opposite side of the shoe, and an in combination defined in claim 16 combined with a screw connected with the first lever and extending therefrom through a slot in the side of the housing, and means mounted on the housing for engaging against the under side of the screwto elevate the same and attached lever, substantially as. de-

21. l[n a machine of the character described, a saw and disk assembly comprising a sleeve threaded at one end and provided with a flange adjacent the opposite end, a

disk having a consecutive series of ratchet teeth placed against the flange, a spacing,

collar located against the disk, a.saw having the same number of teeth s the disk located against the collar, a second collar located against the opposite side of the saw, and-a1 binding nut threaded on to the end of the sleeve against said second collar, substantially as described. t

22. In combination, a relatively stationary arbor, a saw and disk assembly containing the elements defined in combination in claim 21 located on said arbor, a bearing washer located against the end of the sleeve, a spring, around the arbor bearing against the washer, and a nut threaded on tothe end of the ar-' bor to compress the spring, substantially as described. V

23. In a machine of the character de scribed, means to successively grind saw teeth on a saw, means forrotatably mount- JOHNP. nnnsrnoiu. 

